Orphanet

Founded in France by INSERM in 1997 and expanded into a 40-country European consortium from 2000, Orphanet is the world's leading reference portal for rare diseases and orphan drugs.

At its core, Orphanet maintains one of the most comprehensive rare disease databases in the world. Each entry typically includes clinical descriptions, genetic causes where known, epidemiology, diagnostic pathways, differential diagnoses, and summaries of available management options. It also provides information on orphan drugs, including regulatory status and availability across different regions.It catalogues 6,528 rare diseases, 4,512 associated genes, 8,722 expert centres, and 36,595 diagnostic tests, attracting 2.8 million page views monthly from clinicians, researchers, and patients worldwide.

A key feature is the ORPHA code system, a structured classification framework that assigns unique identifiers to rare diseases. This system is widely used in Europe to support clinical coding, epidemiological tracking, and interoperability between health records, registries, and research datasets—helping to standardise data that is often fragmented due to disease rarity.

Orphanet also functions as a healthcare mapping service, listing expert centres, reference networks, diagnostic laboratories, and specialist services across multiple countries. This helps patients and clinicians locate appropriate expertise, which is particularly important given the scarcity of specialists in many rare conditions.

In addition, it supports research and public health planning by providing aggregated epidemiological data, supporting rare disease registries, and enabling cross-country comparisons of disease prevalence and healthcare provision. These datasets are frequently used by researchers, policymakers, and healthcare planners.